Bolt actuated ejection port cover

ABSTRACT

METHOD AND APPARATUS FOR COVERING AN EJECTION PORT IN THE RECEIVE OF A FIREARM. THE COVER IS BOLT-ACTUATED, AND TELESCOPICALLY MOVES IN CONCERT WITH THE BOLT AS IT IS RETRACTED FROM THE CLOSED BREECH (BATTERY) POSITION TOWARDS THE OPEN BREECH POSITION. A POINT IS REACHED IN THE TRAVEL OF THE COVER, WHEN ITS TRAVEL IS RESTRICTED BY AN ABUTMENT IN THE INTERIOR WALL OF THE RECEIVER, WHEREUPON THE COVER IS CAUSED TO ROTATE WITH THE FURTHER WITHDRAWAL OF THE BOLT, SUBSTANTIALLY UNCOVERING THE ENTIRE EJECTION PORT AREA.

J. M. ALDAY Nov. 16, 1971 3 Shoots-Shoot 1 Filed April 6, 1970 .r O t mV h I James M. Alday Nov. 16, 1971 I J. M. ALDAY 3,619,926

BOLT ACTUAIED EJECTION PORT COVER Filed April 6, 1970 3 Sheets-Sheet r:

Inventor: James M. Aldag Attorneys NOV. 16, 1971 J, ALDAY BOLT AGTUATEDEJECTION PORT COVER 3 Sheets-Sheet 5 Filed April 6, 1970 Inventor JamesM. Aldag Atto rney United States Patent 3,619,926 BOLT ACTUATED EJECTIONPORT COVER James M. Alday, Williamson, N.Y., assignor to Remington ArmsCompany, Inc., Bridgeport, Conn. Filed Apr. 6, 1970, Ser. No. 25,815Int. Cl. F41c 11/00, 27/08 US. C]. 4216 R 7 Claims ABSTRACT OF THEDISCLOSURE Method and apparatus for covering an ejection port in thereceiver of a firearm. The cover is bolt-actuated, and telescopicallymoves in concert with the bolt as it is retracted from the closed breech(battery) position towards the open breech position. A point is reachedin the travel of the cover, when its travel is restricted by an abutmentin the interior wall of the receiver, whereupon the cover is caused torotate with the further withdrawal of the bolt, substantially uncoveringthe entire ejection port area.

The invention relates to receiver mechanisms and more particularly to amethod and apparatus for covering an ejection port in the receiver of afirearm.

The prior art generally discloses two types of covering mechanisms:

(a) those lids which are hinged to the receiver and hip open to exposethe ejection port, and

(b) those covers which telescopically slide within the receiver as the'bolt is retracted towards the open breech position.

The first-mentioned variety of coverings may be seen by reference to thepatents of:

Sampson et al., US. Pat. No. 2,428,683, issued Oct. 7,

Reed, U.S. Pat. No. 2,940,201, issued June 14, 1960; and

ivy, US. Pat. No. 3,030,722, issued Apr. 24, 1962.

The second-mentioned type of coverings are to be seen with reference tothe patents of:

Gans, US. Pat. No. 2,341,767, issued Feb. 15, 1944; and Browning, US.Pat. No. 3,397,473, issued Aug. 20, 1968.

The present invention is a radical departure from the above methods ofcovering the ejection port.

The present system contemplates rotating the port cover to expose theejection window. This rotation can take place either as the sole meansof exposing the port or may be used in conjunction with the telescopingmethod. In the latter case, a portion of the window is first uncoveredby sliding the lid away a limited distance, and then the remainder ofthe window area is exposed by rotating the cover plate away from theport.

A purely rotative method requires that the ejection port present anarrower window, since the degree of rotation within the receiver isusually limited. A larger exposure in the port area necessarily requiresa greater amount of lid travel, and hence cannot usually be accomplishedby rotation alone.

When the telescoping method is combined with the rotative technique, thecover travels only a limited distance of the entire port length. Thereis no need to have a lengthy receiver to provide clearance for the coverin the open breech position.

As is usually the case in systems using a pure telescoping means, thereceiver must be extended to the rear :1 distance equal to that neededfor the cover to clear the port. The extension of the receiver length toaccommodate the cover produces a rifle having an unsightly hump-backedappearance.

The present technique allows for a smooth sloping curvature for therearward portion of the receiver, which not only presents a pleasingstreamlined appearance, but provides for a better balance in thehandling characteristics of the firearm.

The use of the rotation technique alone requires no telescopic movement,and thus, also provides for the aforementioned improvement in therearward portion of the receiver.

The hinged-type covers, while providing for a shorter receiver ofpleasing appearance, are themselves unsightly in their operation.

When the lid flips open, the lid poses an obstruction to the eye, whichmay interfere with the proper sighting of the target. It may alsointerfere with the mounting of telescopic sights upon the gun.

Thus, it is evident that in addition to presenting a new method ofcovering the ejection port, this invention also presents many advantageswhich are not available with the other techniques.

:It is a primary object of this invention to provide a means of coveringthe ejection port in a receiver of a firearm wherein the cover plateneed not extend into the rearward portion of the receiver a distanceequal to the ejection port length.

It is another primary object of this invention to provide a means ofcovering an ejection port by rotation of the cover plate.

It is but another primary object of the invention to provide a receivermechanism for the covering of an ejection port which will allow therearward portion of the receiver to be designed with a smooth slopingcurvature or otherwise present a pleasing streamlined appearance.

R is still another object of this invention to provide a cover platemechanism for the covering of an ejection port which both telescopes androtates within the receiver.

It is another object of this invention to provide an ejection portcovering mechanism which is bolt-assemblyactuated.

These and other objects of the invention Will become apparent and willbe better understood with reference to the subsequent detaileddescription and attached drawings, in which:

FIG. 1 is a perspective view of the receiver with the cover plate (portcover) covering the ejection port;

FIG. 2 is an exploded perspective view of the major parts of thereceiver mechanism;

FIGS. 3 through 6 are sequential cut-away perspective views of the boltand cover arrangement within the receiver wherein:

FIG. 3 shows the bolt and cover arrangement when the bolt is in theclosed breech position, and the cover is fully covering the ejectionport;

FIG. 4 depicts the bolt and cover arrangement when the cover hastelescoped into contact with the abutment of the receiver, and beforethe bolt has been withdrawn far enough for the protuberance on thecircumferential face of the bolt assembly to move in the slot of thecover plate;

FIG. 5 illustrates the bolt and cover arrangement when the cover hasrotated away from the ejection port as the bolt has been furtherwithdrawn to the point where the protuberance of the bolt assembly hasmoved in the dogleg portion of the cover plate slot;

FIG. 6 shows the bolt and cover arrangement with the bolt assembly inthe open breech. position with its protuberance at the end of theelongated portion of the cover slot;

FIG. 7 is a front cut-away view of the receiver mechanism when the boltis in the closed breech position as shown in FIG. 3;

FIG. 8 is a front cut-away view of the receiver mechanism when the boltis in the open breech position as depicted in FIG. 6; and

FIG. 9 is a side cut-away view of the receiver mechanism when the boltis in the open breech position as illustrated in FIG. 6, with the coverplate and spring element shown in section.

Generally speaking, the present invention is for a method and apparatusfor providing the ejection port of a firearm receiver with a covering toprotect the internal mechanism of the gun.

The method suggests having a rotating cover plate contiguous with theejection port of the receiver and substantially covering the entire portarea when the bolt is substantially in the battery position. The bolt ismoved a limited distance from the battery (closed breech) positiontowards the open breech position. The cover plate is rotated tosubstantially expose the entire port area, as the bolt is withdrawntowards the open breech position.

The novelty of the ejection port mechanism resides in the means which,first, telescopically retracts the cover plate a limited distance withinthe receiver in substantial conformity with the retraction of the boltfrom the closed breech position towards the open breech position for thepurpose of exposing a portion of the port area, and then rotating thecover plate away from the port window to substantially expose theremainder of the port area, as the bolt is further retracted towards theopen breech position.

Now referring to FIG. 1, a perspective view of the receiver is shownwith the cover plate as it substantially covers the ejection port. Thecover plate 9 is contiguous with the ejection port 8 of the receiver 7.The cover plate has a rounded cut-away portion 5, which is cut from theplate so as to clear the port window when the plate is rotated, as willbe explained hereinafter. This open portion is covered by the boltassembly 6 which lies directly behind the cover plate. This provides forcomplete coverage of the port area. The bolt is in the closed breechposition, as is also illustrated in FIG. 3. FIG. 3, however, shows thebolt assembly and cover mechanism from the side of the receiver oppositethe port window. Action bars 3 and 4, respectively, telescope the boltassembly within the receiver. This is accomplished by way of projections13 and 14, respectively, which engage the bolt assembly 6 through slots23 and 24 (not shown) as depicted in FIG. 2. The action bars are guidedwithin the receiver by means of slots 33 and 34, respectively, which runthrough the interior wall of the receiver.

The bolt assembly 6 has a bolt head 17 which has locking lugs 18 on theperiphery thereof. The lugs marry with the lugs (not shown) positionedin nose piece 1. The nose piece 1 projects into recess 12, when anchorportion 2 of the barrel extension is fitted to the front of receiver 7.This is accomplished by means of bolt 26, which is fastened to receiver7, and passes through hole 27 of the anchor portion.

Neglecting the receiver housing, the cover mechanism comprises the keyparts of: cover plate 9, bolt assembly 6, and spring 40.

The spring 40 has a pin 21 which fits into hole 22 in the bolt assembly.The pin positively places the spring in relation to the bolt assembly.The spring also possesses a contoured portion 30 which conforms to thecircumferential surface of bolt assembly 6 so as to aid in relating theparts to act together.

The spring is further provided with two leaf-type arms, and 16,respectively. The arm 15 conforms to slot of the bolt assembly toprovide a flush fitting. When the bolt slides within the receiver, thesearms alternately bias the cover plate in what can be described as arocking motion of the spring 40 about bolt assembly 6 so that in theextreme rearward position of the bolt, the rear arm is pushed down bythe sloping top interior of the receiver, placing a greater load on thefront arm, holding the cover securely against the receiver.

The cover plate 9 fits over the spring and bolt assembly as shown in thevarious views. The cover plate is con toured for rotation within thereceiver.

The arms 15 and 16 contact the underside (concave face) of the coverplate as the bolt is withdrawn from the closed breech position (FIG. 3)towards the open breech position (FIG. 6). At the extreme rear end ofthe bolt travel, the arm 16 of the spring contacts the interior wall ofthe receiver, as it rides off the inside surface of cover 9. The actionof the spring serves several purposes:

(1) It forces the cover plate against the interior wall of the receiverso that it will have a snug fit. This will prevent the cover fromrattling.

(2) It influences the plate to move in conformity with the bolt as ittelescopes within the receiver; and

(3) It causes the cover plate to make positive engagement with travellimiting abutments within the receiver wall (this will be described morefully hereinafter with reference to FIGS. 3 through 6).

The cover plate has a slot 25 extending longitudinally therethrough. Theslot is composed of two sections:

(a) a dog-leg bend at the fore-end of the plate; and

(b) a straight elongated slot portion extending therefrom.

The protuberance 19 of the bolt assembly fits into the slot for thepurpose of camming the plate to rotate away from the ejection port asthe bolt is withdrawn from the closed breech position at the point whenthe cover plate becomes restrained from sliding in concerted movementwith the bolt (see FIGS. 4 and 5).

OPERATION OF THE MECHANISM Referring to FIG. 3, the bolt is shown in theclosed breech (battery) position. The cover plate 9 is resting upon thebolt assembly, and is covering the ejection port window 8 as shown inFIG. 1. The bolt is withdrawn from the closed breech position towardsthe open breech position as depicted by arrow 41. As the bolt iswithdrawn, the cover plate is forced to move with the bolt assembly dueto the frictional drag effect of the spring (not shown), and from thedrag effect of the camming protuberance on the bolt assembly.

The receiver 7 has an interior Wall 38. At the rear of the receiver Wallis an abutment 39. The cover plate moves in conformity with the boltuntil its back end 37 makes contact with the abutment 39. At this point,the cover is restrained from further telescopic movement within thereceiver. The protuberance 19 of the bolt assembly will now be forced tomove in the slot of the cover plate 9. The slot is composed of a dog-legportion 35 and a straight elongated portion 36 as shown. Theprotuberance 19 is originally resting at the aforemost part of thedog-leg portion of the slot as shown in FIG. 3.

FIG. 4 depicts the cover plate as it has just come up against theabutment. The protuberance 19 has just started to move in slot 35. Thecover plate 9 which has telescoped away from a major portion of the portwindow 8 is now forced to rotate away from the window as shown by arrow42.

As the bolt assembly is further retracted as in FIG. 5, the protuberancemoves to the end of slot portion 35, thus completely rotating the coverplate away from the ejection window as depicted by arrow 43. At thispoint, the ejection port area is completely open, and the protuberanceis positioned at the beginning of slot portion 36.

FIG. 6 illustrates the bolt and cover plate arrangement, when the boltis in the open breech position. The protuberance 19 of the bolt assemblyhas been caused to slide within slot portion 36 to the end thereof. Slotportion 36 does not serve to rotate the cover plate 9, since this is astraight slot portion, and the movement of the protuberance therein doesnot cam the plate.

Slot portion 36 has the function of allowing the bolt to travel to itsextreme open breech position, since without this slot, the bolt assemblywould be restrained from further backward movement after the plate hadrotated clear of the ejection window.

FIGS. 7 and 8 represent frontal cut-away views of the receiver mechanismin its extreme positions. FIG. 7 shows the mechanism as it would appearin the FIG. 3 position, and FIG. 8 depicts the mechanism as it appearsin the FIG. 6 position.

FIG. 9 presents a side cut-away view of the receiver mechanism when thebolt is in the extreme open breech position as shown in FIG. 6.

The bolt assembly 6 is flush against the back of the receiver 7. Thecover plate 9 is flush with the interior wall 38, and its back end 37 isabutting the abutment 39.

Since the cover plate 9 is not drawn all the way back to the extremeopen breech position as is common in the prior art, the outer surface 32of the receiver can have a curvature to give a pleasing appearance asshown.

The preceding sequence of steps (FIGS. 3 through 6) were illustrative ofthe opening of the ejection port window. To close the window, thesequence of steps are almost the reverse of those shown.

The difference being that the cover plate 9 will telescope forward inthe rotated position until the front end of the plate abuts against thetraverse wall of the front end of the receiver recess. At this point,the cover plate is restrained from any further telescoping movementwithin the receiver, and the bolts further forward movement forces theprotuberance 19 back through the slot to cam the cover plate intorotating to the closed window position.

Man modifications and variations of the above mech' anism and methodwill become evident to those skilled in the art. For example, it waspreviously mentioned that the cover plate may be purely rotated withoutthe need for telescoping movement, if the port window is very narrow.The cover plate would then require less rotation to clear the ejectionport. This is so, because with a greater degree of required rotation,the cover plate would abut against the railings or action bar in theinterior of the receiver and would be incapable of further rotationnecessary to clear the port area.

To accomplish the above method, the cover plate would be a greaterlength extending to the present abutment 39 and would be restrained frommoving telescopically within the receiver by means of said abutment.Retraction of the bolt would immediately start the protuberance to movewithin the dog-leg slot of the cover plate, thus rotating the cover freeof the window. The further withdrawal of the bolt would be affected insimilar manner as before except the straight slot portion 36 would nowextend the greater length of the now lengthened cover plate.

Of course, the aforementioned mechanisms can be used with lever-actuatedbolts as well as in pump action firearms. It is also possible to utilizethe exact same mechanism in an autoloading arm, provided the cover isrotated to clear an operating handle afiixed to the bolt, before thehandle is moved rearward sufficiently to contact the end of cut-out 5.

It may also be possible to position the cover plate on the externalsurface of the receiver if so desired.

Variations and modifications as are evident to the skilled practitionerare considered to be within the purview of the scope and spirit of thisinvention as represented by the appended claims.

What is claimed is:

1. In an ejection port covering mechanism for a firearm comprising: ahollow receiver having an ejection port; a bolt slidable within thehollow of the receiver from a closed breech position to an open breechposition; and a cover plate for substantially covering said port whenthe bolt is substantially in the closed breech position,

and which uncovers the port when the bolt is retracted from the closedbreech position towards the open breech position; the improvementcomprising:

means for first telescopically retracting the cover plate a limiteddistance within the receiver in substantial conformity with theretraction of the bolt from the closed breech position towards the openbreech position, so that a portion of the port area is uncoveredthereby, and then rotating the cover plate away from said port tosubstantially uncover the remaining port area, as the bolt is furtherretracted towards the open breech position.

2. A receiver mechanism of a firearm for substantially covering anejection port of said receiver comprising:

a receiver having an ejection port and an interior wall defining acavity for housing the mechanism;

a bolt assembly slidably disposed in said receiver, and

having a protuberance projecting from a circumferential surface thereof;

means for moving the bolt from a closed breech position to an openbreech position;

an elongated telescoping cover plate slidably disposed within the cavityof the receiver for moving a limited distance in the receiver, the coverbeing contiguous to the ejection port when the bolt is substantially inthe closed breech position; said cover having a camming slot forengagement with the protuberance of said bolt, wherein the cover plateis forced to rotate as the protuberance moves within the slot;

an abutment disposed within the interior wall of the receiver andengageable with said cover plate to restrict its telescoping movementwithin the receiver;

biasing means for biasing the cover plate to move in substantialconformity with the bolt as the bolt is withdrawn from the closed breechposition towards the open breech position, and until the cover plateengages said abutment, wherein the cover plate is prevented from slidingany further within the receiver and the protuberance of said boltassembly is then forced to move within the camming slot of said coverplate, whereby the cover plate is caused to rotate clear of the ejectionport as the bolt is further retracted towards the open breech position.

3. The receiver mechanism of claim 2, wherein the biasing means is aflat spring element, a portion of which is contoured and pinned to thecircumferential surface of the bolt assembly so as to act in conformitytherewith.

4. The receiver mechanism of claim 2, wherein the cover plate is curvedin conformity with the curvature of the receiver wall so as to becapable of rotating therein.

5. The receiver mechanism of claim 2, wherein the slot is characterizedby an irregular dog-leg bend in a front portion of the cover plate forthe purpose of providing rotative motion to said plate when theprotuberance is caused to move therein.

6. The receiver mechanism of claim 5, wherein the slot is furthercharacterized by an elongated straight section following said dog-leg'bend as a tail section thereof; whereby the bolt is free to sliderearwardly within the receiver after the cover plate has rotated.

7. The method of uncovering an ejection port of a firearm receivercomprising the steps of:

(a) providing a bolt substantially in the battery position within thereceiver;

(b) providing a cover plate contiguous with said ejection port andsubstantially covering the entire port area when the bolt issubstantially in the battery position;

(c) retracting the bolt a limited distance from the battery positiontowards an open breech position; and

(d) concurrently rotating the cover plate within the receiver so as tosubstantially expose the entire port References Cited UNITED STATESPATENTS 8/1909 Ashton 4216 4/1922 Feederle 4216 8 1,878,038 9/1932 VonFrommer 42-l6 2,288,202 6/ 1942 Mossberg 42-16 2,940,201 6/1960 Reed42-16 BENJAMIN A. BORCHELT, Primary Examiner C. T. JORDAN, AssistantExaminer

